The present invention relates to a planetarium comprising a coordinates projector and more specifically to a planetarium for projecting directions such as north, south, east and west, and the reference coordinates such as bearings, meridian and poles.
A planetarium of the prior art mainly projects the celestial bodies observed from the earth by a star-field projector which is rotatable about its rotary axes, and it also projects coordinates by coordinates projectors. These coordinates projectors are provided on a rotating member which is secured to the star-field projector whereby the coordinates projectors are moved with the star-field projector for projection of the coordinates.
However, recently, diverse motions of a celestial body can be explained through the development of a technology for the projection of the images of celestial bodies as observed from the planets such as the Sun, the Moon, or from Mercury or Venus.
However, the image projection of a celestial body as it travels around a planet other than the earth, as mentioned above, is accompanied by the disadvantages that the coordinates projectors cannot project the reference coordinates such as the bearings on respective planets because of the coordinates projectors being moved with the star-field projector and it is visually difficult to understand the meaning of the motion of a celestial body even in the case where the diurnal motion or change of latitude are simulated on planets other than earth.